*{
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body{
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}
.container{
  width: 100vw;
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;

}
.banner{
  width: 90vw;
  max-width: 1680px;
  height: 432px;
  /* 铺满 */
  background-size: cover;
  /* 图片始终处于中间 */
  background-position: center;
}
.title-box{
  width: 348px;
  height: 432px;
  background-color: rgba(0,0,0,0.45);
  position: absolute;
  top: 0;
  right: 0;
  color: #fff;
  padding-top: 20px;
  /* 背景模糊 */
  backdrop-filter: blur(3px);
}
.title{
  height: 43px;
  line-height: 43px;
  text-indent: 40px;
  font-size: 15px;
  cursor: pointer;
  /*字体不换行 */
  white-space: nowrap;
  overflow: hidden;
  /* 字体大小改变时的过度 */
  transition: font-size 0.1s;
}
.title span{
  font-size: 13px;
  /* 默认隐藏 */
  opacity: 0;
}

 .active{
  color: #ff5c38;
  font-size: 22px;
  /* 加粗等于700 */
  font-weight: bold;
}
.active span{
  opacity: 1;
}
